scipy.interpolate.UnivariateSpline does not do what I expected
Wasted about an hour because I thought a UnivariateSpline
would follow whatever you gave it nicely,
but it just fits a cubic by default to the entire range
no matter how many points you give it.
The way you get it to pass through every point
is to add s=0 which uses many splines spliced together
until the result passes through every point.
This image should illustrate the difference in behavior:
This came up because I was trying to compute the full width at half-maximum
from some samples.
This answer led me to UnivariateSpline, but I missed the s=0.